Figure 1
From: Homer regulates calcium signalling in growth cone turning
Dorsal root ganglia (DRG) growth cone responses to brain derived neurotrophic factor (BDNF), Netrin-1 and Sema-3a in an in vitro turning assay. (A) Representative time-lapse images of DRG growth cones at start (0 minutes) and end (30 minutes). Ti = initial trajectory; Tf = final trajectory; θ = turning angle. Scale bar is 10 μm. (B) growth cone extension/trajectory plots after a 30-minute exposure to gradients of BDNF, vehicle (sensory neuron medium) and Sema-3a. In all cases the micropipette is positioned out of image at upper left quadrant. Quantification of average turning angles (C) and axon extension rates (D). Axon extension rates did not differ significantly after 30 minutes for Netrin-1, BDNF, control or Sema-3a. Positive angles represent attraction; negative angles represent repulsion. Significant differences from control values are marked as: *P < 0.05; **P < 0.005; Mann-Whitney U-test. Error bars indicate standard error of the mean.